Lt. Gov. Jay Dardenne, one of three Republican opponents of Democrat John Bel Edwards during the bruising gubernatorial primary, plans to endorse Edwards at a 9 a.m. press conference on Thursday (Nov. 5), according to a source close to Dardenne.

Although Dardenne originally indicated he wouldn't offer an endorsement in the general election, the source said his thinking on the subject evolved over time. Dardenne and Edwards had been talking since election day (Oct. 24), when Dardenne and Republican candidate Scott Angelle were defeated by Edwards and U.S. Sen. David Vitter.

"He went from 'No I won't' to 'I would if...' to 'I might have to,' to 'Let's do this now,'" the source said.

Both Dardenne and Angelle, were the subject of withering political attacks during the primary launched by U.S. Sen. David Vitter's campaign and the super PACS supporting him. Angelle struck back hard, and Dardenne complained bitterly about the ads during the last two weeks of the campaign during debates before running an ad criticizing Vitter in the last days of the campaign.

The endorsement will take place at "Free Speech Alley" in front of the student union on the campus of LSU in Baton Rouge. Dardenne served as president of LSU's student government when he was in law school.

Endorsing a Democrat in a high-stakes general election carries significant risk for the Republican Dardenne's future political career, particularly if Vitter is ultimately elected governor. But Dardenne has said he has no plans to run for political office beyond his campaign for governor.

Edwards' campaign declined to comment.

Vitter's campaign announced the endorsement on Wednesday of former Gov. Mike Foster. Foster served two terms as governor, from 1996 to 2004. Foster did not endorse in the primary.